Civic EG

alright well i have had my civic sedan for 9 months and has run flawless besides the past two weeks. it all started when my radiator cracked. i replaced it asap and replaced a hose that had torn with a new oem one. my car ran great for a while and then i noticed my radiator fan never came on like it used to so i found out that i have a bad water temp sensor so the fan wouldn't come on and now it works. but the problem now. my car idles at 2k it smokes some times, i smell coolant i believe i have a CEL only after driving for long periods of time and when i try to do a diagnostic test nothing shows up. this all started after i was on the highway and it also seems to back fire when i shift which never happened before.
I really need help on this would be great.

Sounds like it may have overheated and damaged the head gasket.

As for the CEL, often times a bad ecu will not give the code for a CEL, but maybe you're not checking it right by using the right pins in the jumper.
http://civic-eg.com/viewtopic.php?t=1558

A damaged head gasket won't throw a CEL that I know of, so it must be related to another problem.

Keep an eye on your coolant, if it gets low then you know for sure it's being burned off and the head gasket needs replaced.
Or worse yet, the head may be warped or even worse, the block is cracked.

how can i check to see if my head is warped without going to a machine shop?

and i have an exta ecu sitting around so ill try that

you can use a flat edge of a metal ruler to get an idea.